EBCM Exam One Flashcards
If you note a conformational abnormality upon examination of a horse, what should your first next step be?
(Reposition the horse to make sure it is a true conformational abnormality)
What portion of the hoof should be trimmed in a foal with pigeon-toed conformation?
(The medial wall should be mildly lower)
What portion of the hoof should be trimmed in a foal with a splay-footed confirmation?
(The lateral wall should be mildly lower)
What other conformational abnormality is typically paired with a pigeon-toed conformation?
(Base-narrow)
Horses with a base-wide conformational abnormality typically overload which aspect of their lower limb and foot?
(The medial aspect, they land on the inside of their foot; exact opposite for base-narrow → lateral aspect/outside of foot)
Is varus or valgus described as a lateral deviation from the normal forelimb plumb line?
(Valgus; varus is medial deviation from the normal forelimb plumb line)
Does a knock-kneed or bow-legged/bandy-legged horse result from a foal with carpal varus?
(Bow-legged)
What is indicated if you observe sickle hocks in a foal?
(Incomplete ossification of the tarsal cuboidal bones, the crushing that results can lead to sickle hocks in foals so should radiograph them)
What are horses with a splay-footed conformation predisposed to due winging in when in motion?
(Interference or kicking their own legs)
What conformational abnormality is commonly seen in foals at birth but will disappear by 3 months of age but can also be acquired in jumpers?
(Dorsal deviation of the carpus aka buck-kneed, sprung knees, hanging knee, goat knees, or over at the knee)
(T/F) Mild outward rotation of the hindlimbs in a horse is normal.
(T)
A cow-hocked horse (excessive outward rotation of the hocks) will often have what other conformational abnormality?
(Base narrow)
Horses with a toed-in conformation will wing in/out (choose)?
(Out)
Horses with a toed-out conformation will wing in/out (choose)?
(In)
What two characteristics of the trauma causing a fracture determines the configuration of a fracture?
(The direction and amount of force associated with the causing trauma)
(T/F) You should place a splint on a suspect fracture prior to taking field radiographs.
(T)
(T/F) A distal limb fracture should always be splinted.
(T)
If you are placing a splint on a patient with a fracture anywhere from the distal quarter of the cannon bone to the coronary band in a forelimb, where should the splint extend to and from?
(Should extend from the toe to just below the carpus)
If you are placing a splint on a patient with a fracture anywhere from the distal quarter of the radius to mid cannon bone, where should the splints extend to and from?
(Elbow to floor, 2 splints one caudal and one lateral)
Why must a splint placed for a mid to proximal radius fracture extend from the ground to the withers?
(When the horse uses the limb, the muscles in the proximal forelimb will abduct the limb instead of their normal movement due to the incomplete bony column; splint needs to extend past the joint above and below to attempt to mitigate that effect)
What are three differentials if you are presented with a horse with a dropped elbow?
(Radial nerve injury, olecranon fracture, humerus fracture → can place a caudal splint)
When splinting a rear limb with a fracture anywhere from the distal quarter of the cannon bone to the coronary band, the splint is placed on the dorsal/plantar (choose) side.
(Plantar)
Optimally, though not always possible, when transporting a horse with a fracture, the limb with the fracture should be placed at the front/rear (choose) of the trailer.
(Rear → if a hard brake occurs, the horse will shift forward and onto which ever legs are at the front)
What are the two steps to the formation of osteochondrosis?
(Failure of vascular invasion of the cartilage template and then there is not enough blood supply for that cartilage to then ossify into bone so it’s a failure of vascular invasion followed by a failure of ossification)
Horses with OCD are typically slow growing and small/rapidly growing and large (choose).
(Rapidly growing and large)
An excess/deficiency (choose) in energy provided through diet is strongly implicated as a cause of OCD.
(Excess)
An imbalance in what two trace minerals is thought to be a possible cause of OCD?
(Too little copper or too much zinc)
Do subchondral bone cysts occur in areas of gliding or weight bearing?
(Weight bearing, dissecans lesions occur in gliding areas)
What are two reasons you should not use steroids in cases of OCD?
(It can cause ossification of structures that should not be ossified and you don’t want steroids in the joint if you happen to need to go to surgery)
(T/F) A joint with OCD will always have effusion.
(F, most will but some will not especially joints closer to the body)
Flexion/extension (choose) of a joint with OCD will worsen lameness.
(Flexion, due to the effusion usually present and putting further pressure on the joint capsule)
Why may there still be lameness present after blocking a joint with a subchondral bone cyst?
(Because the block can’t block out the bone pain associated with SBCs)
What are two reasons to not immediately jump to surgical correction of OCD/SBC in foals?
(One → they may be able to heal it themselves with time, make sure to monitor/document/radiograph through 18 months of age to ensure proper healing; two → foal bone is much softer than adult bone and that can make discerning the border between normal bone and bone with malacia more difficult)
Debrided OCD beds heal with what type of cartilage?
(Fibrocartilage, not the normal hyaline cartilage found in joints)
What is the minimum amount of time a horse needs to be stall rested post OCD surgery?
(60 days, no turnout, then gradual return to work)
Why is the rehabilitation period longer for subchondral bone cysts corrected by surgery compared to OCD?
(Because SBCs are related to weight bearing surfaces whereas OCD are gliding surfaces)
What main pathology being present along with an OCD lesion or SBC decreases the prognosis?
(Osteoarthritis)
Bilateral OCD lesions occur in about 50% of cases, so you should take radiographs of the contralateral joint. You take a radiograph of a contralateral joint and do not see any changes, can you stop there?
(No, if only the cartilage is sheared off, you will not be able to tell if there is an OCD lesion, further testing (flexion tests, IA blocks, etc.) is warranted especially if lameness noted on contralateral limb)
If a horse has multiple joints with OCD lesions, where else should you check for OCD?
(Their neck)
OCD/SBC (choose) is very common in the femoropatellar joints.
(OCD, SBC uncommon)
OCD lesions of the lateral/medial (choose) trochlear ridge in the femoropatellar joint are much more common.
(Lateral)
If you find OCD lesions on the trochlear ridges of the femoropatellar joint, you should explore what structure for additional lesions?
(The patella, look for kissing lesions)
OCD/SBC (choose) is very common in the femorotibial joints
(SBC, OCD uncommon)
SBC lesions of the lateral/medial (choose) femorotibial joint are more typical.
(Medial)
(T/F) The marginal sclerosis of an SBC lesion may demonstrate its maturity.
(T)
OCD/SBC (choose) is very common in the tibiotarsal joint.
(OSD, SBC on trochlear ridges are uncommon)
OCD and SBC of the radiohumeral joint is generally less common in horses compared to other joints but they do occur, give the location that either would most likely occur at.
(SBC → medial proximal radial condyle, OCD → distal humeral condyle)
(T/F) Surgery is not an option for OCD/SBC of the radiohumeral joint so exhaustive conservative therapy is pursued.
(T, prognosis ain’t great)
OCD/SBC (choose) is more likely to affect the femoral head in the coxofemoral joint.
(SBC)
What are some things that can impact the rate of growth of a horse’s hoof?
(Time of year, pathology, nutrition, and job/exercise level)
Why are horse’s hooves trimmed?
(To remove excess length, to remove distortion, to improve the base of support, to prevent chipping, and to remove disease/deteriorated areas)
Why do horses wear shoes?
(Protection, treatment, traction, and to alter gait)
(T/F) If a horse does not fall into a typical category for why horses wear shoes (protection, treatment, traction, and to alter gait), they should not be shod.
(T, cons outweigh the pros)
What are some consequences of horse shoes?
(Increases shock/concussion to the distal limb, traumatic hoof wall loss, puncture wounds from clips/nails, spring/twisted shoe, injury when kicking, nail too close to sensitive structures)
What is the main difference in a hoof trim if you are going to put a shoe on or not?
(Shoe → trim shorter, should be flat with a sharp edge, no shoe → outer edge should be rounded to prevent chipping and should be left longer to allow for wearing)
What does it mean that you want to achieve a matched hoof pastern axis?
(The dorsal wall of the hoof will match the angle of the bony column of the foot → allows spreading of the load evenly between all structures of the foot)
What should the length and angle of the heel be in relation to the dorsal hoof wall in an appropriately trimmed horse hoof?
(Angle should match the dorsal hoof wall and the heel would optimally be about ⅓ the length of the dorsal hoof wall)
The frog would optimally extend over what percentage of the length of the hoof?
(60%)
(T/F) A positive palmar angle is optimal, average is usually 3-5 degrees.
(T, do not want a flat/negative palmar angle)
What is a broken back hoof pastern axis?
(When the angle of P2 and P1 are steeper than P3)
What structures are overloaded with a broken back HPA and what conditions can that predispose the horse to?
(Overloaded → DDFT, navicular bone, P2, and P1; conditions → navicular dz, ring bone, coffin joint inflammation, hoof cracks, and sheared heels)
What is a broken forward hoof pastern axis?
(When the angle of P3 is steeper than that of P1 and P2 → stresses the suspensory ligament in particular)
What is the main positive function of a hoof pad?
(Recruits the sole and frog in load sharing, others → protect and support, align the hoof pastern axis, protect wounds, act as artificial sole depth, aid with shock dissipation)
What substance can be added to packing material for a hoof pad that is a good antimicrobial?
(Copper sulfate)
Why must silicone be used under a hoof pad?
(Bc it does not bond to the sole)
Why is oakum a good option for horses with white line disease and/or abscesses?
(It allows for drainage → is non-sealing)
What are some shoe options that can ease breakover?
(Rolled toe, rocker toe, square/blunt toe, and bar shoes)
How should a hoof be trimmed to fix a broken back HPA?
(Trim the toe, not the heel; can also use wedges)
How should a hoof be trimmed to fix a broken forward HPA?
(Trim the heel, not the toe; should aim to also treat the primary cause if it related to chronic lameness or a flexural deformity)
In a wry foot, is the portion of the hoof that rolls under the foot or the portion of the hoof that flares at an increased risk for development of a quarter crack?
(The portion that rolls under the foot)
What is the typical etiology for wry feet?
(Base narrow or base wide conformation)
You have a wry foot due to a base wide conformation, when shoeing should the shoe be placed with excess shoe on the lateral or medial hoof wall?
(You’ll want excess shoe on the medial hoof wall because that will be the wall that is rolling under in a base wide conformation, flare of the lateral wall should be trimmed)
What is the goal for shoeing to fix sheared heels?
(Decreasing the load of the displaced heel)
What do flat feet predispose a horse to?
(Sole bruising and subsequent lameness)